The present invention relates to a refrigerant cycle apparatus constituted by sequentially connecting an electric compressor, a gas cooler, a pressure reducing device, an evaporator, and an accumulator in an annular form through pipes, and driving a motor of the electric compressor by an inverter module.
Recently, as an air conditioner for an electric automobile, a refrigerant cycle apparatus having an electric compressor mounted thereon to be driven by power from a battery has been developed. This refrigerant cycle apparatus is constituted by sequentially connecting the electric compressor, a gas cooler, a pressure reducing device (expansion valve or the like), an evaporator, and an accumulator in an annular form through pipes. A DC voltage from the battery is converted into a three-phase pseudo AC voltage by an inverter module and applied to the electric compressor, whereby a motor in the electric compressor is driven to start compression running of a refrigerant.
The inverter module is constituted by molding a switching element group comprising a switching element and a diode for switching serge absorption in a mold package (e.g., see Japanese Patent No. 3341327).
The inverter module generates heat when it is run, and thus the heat must be released. In other words, because of the heat generation, there is the danger that the heat may fill the inverter module to damage the switching element group. Thus, conventionally, a device for cooling the inverter module by air or water has been provided. The inverter module has been cooled by this device, thereby preventing a problem of damaging the inverter module.
However, when such a device for cooling the inverter module by air or water is installed, an installation space is considerably enlarged by the device, creating a difficulty of miniaturizing the refrigerant cycle apparatus.